diff --git a/qiskit_ibm_runtime/estimator.py b/qiskit_ibm_runtime/estimator.py
index 1e4160332..622311b4b 100644
--- a/qiskit_ibm_runtime/estimator.py
+++ b/qiskit_ibm_runtime/estimator.py
@@ -16,7 +16,6 @@
 import os
 from typing import Optional, Dict, Sequence, Any, Union
 import logging
-import typing
 
 from qiskit.circuit import QuantumCircuit
 from qiskit.quantum_info.operators.base_operator import BaseOperator
@@ -31,9 +30,6 @@
 # pylint: disable=unused-import,cyclic-import
 from .session import Session
 
-if typing.TYPE_CHECKING:
-    from qiskit.opflow import PauliSumOp
-
 logger = logging.getLogger(__name__)
 
 
@@ -118,7 +114,7 @@ def __init__(
     def run(  # pylint: disable=arguments-differ
         self,
         circuits: QuantumCircuit | Sequence[QuantumCircuit],
-        observables: BaseOperator | PauliSumOp | Sequence[BaseOperator | PauliSumOp],
+        observables: BaseOperator | Sequence[BaseOperator],
         parameter_values: Sequence[float] | Sequence[Sequence[float]] | None = None,
         **kwargs: Any,
     ) -> RuntimeJob:
@@ -154,7 +150,7 @@ def run(  # pylint: disable=arguments-differ
     def _run(  # pylint: disable=arguments-differ
         self,
         circuits: Sequence[QuantumCircuit],
-        observables: Sequence[BaseOperator | PauliSumOp],
+        observables: Sequence[BaseOperator],
         parameter_values: Sequence[Sequence[float]],
         **kwargs: Any,
     ) -> RuntimeJob:
diff --git a/qiskit_ibm_runtime/fake_provider/fake_backend.py b/qiskit_ibm_runtime/fake_provider/fake_backend.py
index 023d4beee..58b7ac19b 100644
--- a/qiskit_ibm_runtime/fake_provider/fake_backend.py
+++ b/qiskit_ibm_runtime/fake_provider/fake_backend.py
@@ -29,7 +29,6 @@
 from qiskit import pulse
 from qiskit.exceptions import QiskitError
 from qiskit.utils import optionals as _optionals
-from qiskit.providers import basicaer
 from qiskit.transpiler import Target
 from qiskit.providers import Options
 from qiskit.providers.backend_compat import convert_to_target
@@ -39,6 +38,11 @@
     decode_pulse_defaults,
 )
 
+try:
+    from qiskit.providers.basicaer import QasmSimulatorPy as BasicSimulator
+except ImportError:
+    from qiskit.providers.basic_provider import BasicSimulator
+
 
 class _Credentials:
     def __init__(self, token: str = "123456", url: str = "https://") -> None:
@@ -128,7 +132,7 @@ def _setup_sim(self) -> None:
                 self.set_options(noise_model=noise_model)
 
         else:
-            self.sim = basicaer.QasmSimulatorPy()
+            self.sim = BasicSimulator()
 
     def _get_conf_dict_from_json(self) -> dict:
         if not self.conf_filename:
@@ -205,7 +209,7 @@ def _default_options(cls) -> Options:
 
             return AerSimulator._default_options()
         else:
-            return basicaer.QasmSimulatorPy._default_options()
+            return BasicSimulator._default_options()
 
     @property
     def dtm(self) -> float:
@@ -304,12 +308,12 @@ def run(self, run_input, **options):  # type: ignore
 
         This method runs circuit jobs (an individual or a list of QuantumCircuit
         ) and pulse jobs (an individual or a list of Schedule or ScheduleBlock)
-        using BasicAer or Aer simulator and returns a
+        using BasicAer simulator/ BasicSimulator or Aer simulator and returns a
         :class:`~qiskit.providers.Job` object.
 
         If qiskit-aer is installed, jobs will be run using AerSimulator with
         noise model of the fake backend. Otherwise, jobs will be run using
-        BasicAer simulator without noise.
+        BasicAer simulator/ BasicSimulator simulator without noise.
 
         Currently noisy simulation of a pulse job is not supported yet in
         FakeBackendV2.
@@ -475,7 +479,7 @@ def _setup_sim(self) -> None:
                 # it when run() is called
                 self.set_options(noise_model=noise_model)
         else:
-            self.sim = basicaer.QasmSimulatorPy()
+            self.sim = BasicSimulator()
 
     def properties(self) -> BackendProperties:
         """Return backend properties"""
@@ -536,7 +540,7 @@ def _default_options(cls) -> Options:
 
             return QasmSimulator._default_options()
         else:
-            return basicaer.QasmSimulatorPy._default_options()
+            return BasicSimulator._default_options()
 
     def run(self, run_input, **kwargs):  # type: ignore
         """Main job in simulator"""
diff --git a/qiskit_ibm_runtime/qpy/binary_io/circuits.py b/qiskit_ibm_runtime/qpy/binary_io/circuits.py
index 11591e103..f51f48b7d 100644
--- a/qiskit_ibm_runtime/qpy/binary_io/circuits.py
+++ b/qiskit_ibm_runtime/qpy/binary_io/circuits.py
@@ -24,7 +24,6 @@
 import numpy as np
 
 from qiskit import circuit as circuit_mod
-from qiskit import extensions
 from qiskit.circuit import library, controlflow, CircuitInstruction, ControlFlowOp
 from qiskit.circuit.classical import expr
 from qiskit.circuit.classicalregister import ClassicalRegister, Clbit
@@ -34,7 +33,6 @@
 from qiskit.circuit.instruction import Instruction
 from qiskit.circuit.quantumcircuit import QuantumCircuit
 from qiskit.circuit.quantumregister import QuantumRegister, Qubit
-from qiskit.extensions import quantum_initializer
 from qiskit.quantum_info.operators import SparsePauliOp
 from qiskit.synthesis import evolution as evo_synth
 from qiskit.transpiler.layout import Layout, TranspileLayout
@@ -301,10 +299,6 @@ def _read_instruction(  # type: ignore[no-untyped-def]
         gate_class = getattr(library, gate_name)
     elif hasattr(circuit_mod, gate_name):
         gate_class = getattr(circuit_mod, gate_name)
-    elif hasattr(extensions, gate_name):
-        gate_class = getattr(extensions, gate_name)
-    elif hasattr(quantum_initializer, gate_name):
-        gate_class = getattr(quantum_initializer, gate_name)
     elif hasattr(controlflow, gate_name):
         gate_class = getattr(controlflow, gate_name)
     else:
@@ -626,8 +620,6 @@ def _write_instruction(  # type: ignore[no-untyped-def]
         (
             not hasattr(library, gate_class_name)
             and not hasattr(circuit_mod, gate_class_name)
-            and not hasattr(extensions, gate_class_name)
-            and not hasattr(quantum_initializer, gate_class_name)
             and not hasattr(controlflow, gate_class_name)
         )
         or gate_class_name == "Gate"
diff --git a/qiskit_ibm_runtime/transpiler/passes/scheduling/__init__.py b/qiskit_ibm_runtime/transpiler/passes/scheduling/__init__.py
index e22b816d8..90308b73c 100644
--- a/qiskit_ibm_runtime/transpiler/passes/scheduling/__init__.py
+++ b/qiskit_ibm_runtime/transpiler/passes/scheduling/__init__.py
@@ -43,7 +43,6 @@
     from qiskit_ibm_runtime.transpiler.passes.scheduling import PadDelay
     from qiskit_ibm_runtime.fake_provider import FakeJakarta
 
-
     backend = FakeJakarta()
 
     # Temporary workaround for mock backends. For real backends this is not required.
diff --git a/qiskit_ibm_runtime/transpiler/passes/scheduling/dynamical_decoupling.py b/qiskit_ibm_runtime/transpiler/passes/scheduling/dynamical_decoupling.py
index 40c24d54c..b7406263a 100644
--- a/qiskit_ibm_runtime/transpiler/passes/scheduling/dynamical_decoupling.py
+++ b/qiskit_ibm_runtime/transpiler/passes/scheduling/dynamical_decoupling.py
@@ -23,12 +23,16 @@
 from qiskit.circuit.reset import Reset
 from qiskit.dagcircuit import DAGCircuit, DAGNode, DAGInNode, DAGOpNode
 from qiskit.quantum_info.operators.predicates import matrix_equal
-from qiskit.quantum_info.synthesis import OneQubitEulerDecomposer
 from qiskit.transpiler.exceptions import TranspilerError
 from qiskit.transpiler.instruction_durations import InstructionDurations
 from qiskit.transpiler.passes.optimization import Optimize1qGates
 from qiskit.transpiler import CouplingMap
 
+try:
+    from qiskit.quantum_info.synthesis import OneQubitEulerDecomposer
+except ImportError:
+    from qiskit.synthesis import OneQubitEulerDecomposer
+
 from .block_base_padder import BlockBasePadder
 
 
diff --git a/test/integration/test_options.py b/test/integration/test_options.py
index 00db91774..89c90006e 100644
--- a/test/integration/test_options.py
+++ b/test/integration/test_options.py
@@ -13,12 +13,12 @@
 """Tests for job functions using real runtime service."""
 
 from qiskit import QuantumCircuit
-from qiskit.providers.fake_provider import FakeManila
 
 from qiskit.circuit.library import RealAmplitudes
 from qiskit.quantum_info import SparsePauliOp
 from qiskit_aer.noise import NoiseModel
 from qiskit_ibm_runtime import Session, Sampler, Options, Estimator
+from qiskit_ibm_runtime.fake_provider import FakeManila
 from qiskit_ibm_runtime.exceptions import RuntimeJobFailureError
 
 from ..ibm_test_case import IBMIntegrationTestCase
diff --git a/test/unit/mock/fake_api_backend.py b/test/unit/mock/fake_api_backend.py
index 6ad2e4f5c..75b06c9d0 100644
--- a/test/unit/mock/fake_api_backend.py
+++ b/test/unit/mock/fake_api_backend.py
@@ -15,7 +15,7 @@
 from datetime import datetime as python_datetime
 from dataclasses import dataclass
 
-from qiskit.providers.fake_provider import FakeLima
+from qiskit_ibm_runtime.fake_provider import FakeLima
 
 
 @dataclass
diff --git a/test/unit/test_backend.py b/test/unit/test_backend.py
index bbf86631c..3eda26ed2 100644
--- a/test/unit/test_backend.py
+++ b/test/unit/test_backend.py
@@ -16,11 +16,10 @@
 import warnings
 
 from qiskit import transpile, qasm3, QuantumCircuit
-from qiskit.providers.fake_provider import FakeManila
 from qiskit.providers.models import BackendStatus
 
 from qiskit_ibm_runtime.exceptions import IBMBackendValueError
-
+from qiskit_ibm_runtime.fake_provider import FakeManila
 from qiskit_ibm_runtime.ibm_backend import IBMBackend
 
 from ..ibm_test_case import IBMTestCase
diff --git a/test/unit/test_backend_retrieval.py b/test/unit/test_backend_retrieval.py
index de809d096..0de18f164 100644
--- a/test/unit/test_backend_retrieval.py
+++ b/test/unit/test_backend_retrieval.py
@@ -15,7 +15,7 @@
 import uuid
 
 from qiskit.providers.exceptions import QiskitBackendNotFoundError
-from qiskit.providers.fake_provider import FakeLima
+from qiskit_ibm_runtime.fake_provider import FakeLima
 
 from .mock.fake_runtime_service import FakeRuntimeService
 from .mock.fake_api_backend import FakeApiBackendSpecs
diff --git a/test/unit/test_data_serialization.py b/test/unit/test_data_serialization.py
index eaeaed192..72d5bf687 100644
--- a/test/unit/test_data_serialization.py
+++ b/test/unit/test_data_serialization.py
@@ -25,11 +25,11 @@
 from qiskit.circuit import Parameter, QuantumCircuit
 
 from qiskit.circuit.library import EfficientSU2, CXGate, PhaseGate, U2Gate
-from qiskit.providers.fake_provider import FakeNairobi
 from qiskit.quantum_info import SparsePauliOp, Pauli, Statevector
 from qiskit.result import Result
 from qiskit_aer.noise import NoiseModel
 from qiskit_ibm_runtime.utils import RuntimeEncoder, RuntimeDecoder
+from qiskit_ibm_runtime.fake_provider import FakeNairobi
 from .mock.fake_runtime_client import CustomResultRuntimeJob
 from .mock.fake_runtime_service import FakeRuntimeService
 from ..ibm_test_case import IBMTestCase
@@ -96,13 +96,6 @@ def test_coder_qc(self):
     def test_coder_operators(self):
         """Test runtime encoder and decoder for operators."""
 
-        # filter warnings triggered by opflow imports
-        with warnings.catch_warnings():
-            warnings.filterwarnings("ignore", category=DeprecationWarning)
-            from qiskit.opflow import PauliSumOp  # pylint: disable=import-outside-toplevel
-
-            deprecated_op = PauliSumOp(SparsePauliOp(Pauli("XYZX"), coeffs=[2]))
-
         coeff_x = Parameter("x")
         coeff_y = coeff_x + 1
 
@@ -110,7 +103,6 @@ def test_coder_operators(self):
             SparsePauliOp(Pauli("XYZX"), coeffs=[2]),
             SparsePauliOp(Pauli("XYZX"), coeffs=[coeff_y]),
             SparsePauliOp(Pauli("XYZX"), coeffs=[1 + 2j]),
-            deprecated_op,
         )
 
         for operator in subtests:
diff --git a/test/unit/test_ibm_primitives.py b/test/unit/test_ibm_primitives.py
index 9e73464d8..5850ff1b9 100644
--- a/test/unit/test_ibm_primitives.py
+++ b/test/unit/test_ibm_primitives.py
@@ -23,7 +23,7 @@
 from qiskit.circuit import QuantumCircuit
 
 from qiskit.quantum_info import SparsePauliOp
-from qiskit.providers.fake_provider import FakeManila
+from qiskit_ibm_runtime.fake_provider import FakeManila
 
 from qiskit_ibm_runtime import (
     Sampler,
diff --git a/test/unit/test_options.py b/test/unit/test_options.py
index 572bd0950..15eb86202 100644
--- a/test/unit/test_options.py
+++ b/test/unit/test_options.py
@@ -16,12 +16,13 @@
 
 from ddt import data, ddt
 from qiskit.providers import BackendV1
-from qiskit.providers.fake_provider import FakeManila, FakeNairobiV2
+
 from qiskit.transpiler import CouplingMap
 from qiskit_aer.noise import NoiseModel
 
 from qiskit_ibm_runtime import Options, RuntimeOptions
 from qiskit_ibm_runtime.utils.qctrl import _warn_and_clean_options
+from qiskit_ibm_runtime.fake_provider import FakeManila, FakeNairobiV2
 
 from ..ibm_test_case import IBMTestCase
 from ..utils import dict_keys_equal, dict_paritally_equal, flat_dict_partially_equal
diff --git a/test/unit/test_runtime_ws.py b/test/unit/test_runtime_ws.py
index 27c3230c4..3dc232a1b 100644
--- a/test/unit/test_runtime_ws.py
+++ b/test/unit/test_runtime_ws.py
@@ -15,7 +15,6 @@
 import time
 from unittest.mock import MagicMock
 
-from qiskit.providers.fake_provider import FakeQasmSimulator
 from qiskit.quantum_info import SparsePauliOp
 from qiskit_ibm_runtime import (
     RuntimeJob,
@@ -235,7 +234,6 @@ def _get_job(self, callback=None, job_id=JOB_ID_PROGRESS_DONE, backend=None):
         params = ClientParameters(
             channel="ibm_quantum", token="my_token", url=MockWsServer.VALID_WS_URL
         )
-        backend = backend or FakeQasmSimulator()
         job = RuntimeJob(
             backend=backend,
             api_client=BaseFakeRuntimeClient(),
diff --git a/test/unit/test_session.py b/test/unit/test_session.py
index fc62751e5..5e228acbb 100644
--- a/test/unit/test_session.py
+++ b/test/unit/test_session.py
@@ -17,8 +17,8 @@
 from concurrent.futures import ThreadPoolExecutor, wait
 
 from unittest.mock import MagicMock, Mock, patch
-from qiskit.providers.fake_provider import FakeManila
 
+from qiskit_ibm_runtime.fake_provider import FakeManila
 from qiskit_ibm_runtime import Session
 from qiskit_ibm_runtime.ibm_backend import IBMBackend
 from qiskit_ibm_runtime.utils.default_session import _DEFAULT_SESSION
diff --git a/test/unit/transpiler/passes/scheduling/control_flow_test_case.py b/test/unit/transpiler/passes/scheduling/control_flow_test_case.py
deleted file mode 100644
index b64822883..000000000
--- a/test/unit/transpiler/passes/scheduling/control_flow_test_case.py
+++ /dev/null
@@ -1,36 +0,0 @@
-# This code is part of Qiskit.
-#
-# (C) Copyright IBM 2022, 2023.
-#
-# This code is licensed under the Apache License, Version 2.0. You may
-# obtain a copy of this license in the LICENSE.txt file in the root directory
-# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
-#
-# Any modifications or derivative works of this code must retain this
-# copyright notice, and modified files need to carry a notice indicating
-# that they have been altered from the originals.
-
-"""Enhanced test case for control flow circuits."""
-
-from typing import Any, Optional
-
-from qiskit import QuantumCircuit
-from qiskit.test._canonical import canonicalize_control_flow
-
-from .....ibm_test_case import IBMTestCase
-
-
-class ControlFlowTestCase(IBMTestCase):
-    """Test case that enforces control flow canonicalization of quantum circuits."""
-
-    def assertEqual(  # pylint: disable=arguments-differ
-        self, first: Any, second: Any, msg: Optional[str] = None
-    ) -> None:
-        """Modify assertEqual to canonicalize the quantum circuit."""
-        if isinstance(first, QuantumCircuit):
-            first = canonicalize_control_flow(first)
-
-        if isinstance(second, QuantumCircuit):
-            second = canonicalize_control_flow(second)
-
-        super().assertEqual(first, second, msg=msg)  # pylint: disable=no-value-for-parameter
diff --git a/test/unit/transpiler/passes/scheduling/test_dynamical_decoupling.py b/test/unit/transpiler/passes/scheduling/test_dynamical_decoupling.py
index 145420478..df42b629b 100644
--- a/test/unit/transpiler/passes/scheduling/test_dynamical_decoupling.py
+++ b/test/unit/transpiler/passes/scheduling/test_dynamical_decoupling.py
@@ -35,13 +35,13 @@
     DynamicCircuitInstructionDurations,
 )
 
-from .control_flow_test_case import ControlFlowTestCase
+from .....ibm_test_case import IBMTestCase
 
 # pylint: disable=invalid-name,not-context-manager
 
 
 @ddt
-class TestPadDynamicalDecoupling(ControlFlowTestCase):
+class TestPadDynamicalDecoupling(IBMTestCase):
     """Tests PadDynamicalDecoupling pass."""
 
     def setUp(self):
diff --git a/test/unit/transpiler/passes/scheduling/test_scheduler.py b/test/unit/transpiler/passes/scheduling/test_scheduler.py
index e9ed82e1f..3170a3e5f 100644
--- a/test/unit/transpiler/passes/scheduling/test_scheduler.py
+++ b/test/unit/transpiler/passes/scheduling/test_scheduler.py
@@ -15,12 +15,12 @@
 from unittest.mock import patch
 
 from qiskit import ClassicalRegister, QuantumCircuit, QuantumRegister, transpile
-from qiskit.providers.fake_provider import FakeJakarta
 from qiskit.pulse import Schedule, Play, Constant, DriveChannel
 from qiskit.transpiler.passes import ConvertConditionsToIfOps
 from qiskit.transpiler.passmanager import PassManager
 from qiskit.transpiler.exceptions import TranspilerError
 
+from qiskit_ibm_runtime.fake_provider import FakeJakarta
 from qiskit_ibm_runtime.transpiler.passes.scheduling.pad_delay import PadDelay
 from qiskit_ibm_runtime.transpiler.passes.scheduling.scheduler import (
     ALAPScheduleAnalysis,
@@ -30,12 +30,12 @@
     DynamicCircuitInstructionDurations,
 )
 
-from .control_flow_test_case import ControlFlowTestCase
+from .....ibm_test_case import IBMTestCase
 
 # pylint: disable=invalid-name,not-context-manager
 
 
-class TestASAPSchedulingAndPaddingPass(ControlFlowTestCase):
+class TestASAPSchedulingAndPaddingPass(IBMTestCase):
     """Tests the ASAP Scheduling passes"""
 
     def test_if_test_gate_after_measure(self):
@@ -808,7 +808,7 @@ def test_c_if_plugin_conversion_with_transpile(self):
         self.assertEqual(expected, scheduled)
 
 
-class TestALAPSchedulingAndPaddingPass(ControlFlowTestCase):
+class TestALAPSchedulingAndPaddingPass(IBMTestCase):
     """Tests the ALAP Scheduling passes"""
 
     def test_alap(self):